Inductively Coupled Plasma Mass Spectrometry Research Articles

Advancing Simultaneous Extraction and Sequential Single-Particle ICP-MS Analysis for Metallic Nanoparticle Mixtures in Plant Tissues.

Engineered nanoparticles (ENPs) have been increasingly used in agricultural operations, leading to an urgent need for robust methods to analyze co-occurring ENPs in plant tissues. In response, this study advanced the simultaneous extraction of coexisting silver, cerium oxide, and copper oxide ENPs in lettuce shoots and roots using macerozyme R-10 and analyzed them by single-particle inductively coupled plasma-mass spectrometry (ICP-MS). Additionally, the standard stock suspensions of the ENPs were stabilized with citrate, and the long-term stability (up to 5 months) was examined for the first time. The method performance results displayed satisfactory accuracies and precisions and achieved low particle concentration and particle size detection limits. Significantly, the oven drying process was proved not to impact the properties of the ENPs; therefore, oven-dried lettuce tissues were used in this study, which markedly expanded the applicability of this method. This robust methodology provides a timely approach to characterize and quantify multiple coexisting ENPs in plants.

Comparative mathematical modeling of causal association between metal exposure and development of chronic kidney disease

BackgroundPrevious studies have identified several genetic and environmental risk factors for chronic kidney disease (CKD). However, little is known about the relationship between serum metals and CKD risk.MethodsWe investigated associations between serum metals levels and CKD risk among 100 medical examiners and 443 CKD patients in the medical center of the First Hospital Affiliated to China Medical University. Serum metal concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS). We analyzed factors influencing CKD, including abnormalities in Creatine and Cystatin C, using univariate and multiple analysis such as Lasso and Logistic regression. Metal levels among CKD patients at different stages were also explored. The study utilized machine learning and Bayesian Kernel Machine Regression (BKMR) to assess associations and predict CKD risk based on serum metals. A chained mediation model was applied to investigate how interventions with different heavy metals influence renal function indicators (creatinine and cystatin C) and their impact on diagnosing and treating renal impairment.ResultsSerum potassium (K), sodium (Na), and calcium (Ca) showed positive trends with CKD, while selenium (Se) and molybdenum (Mo) showed negative trends. Metal mixtures had a significant negative effect on CKD when concentrations were all from 30th to 45th percentiles compared to the median, but the opposite was observed for the 55th to 60th percentiles. For example, a change in serum K concentration from the 25th to the 75th percentile was associated with a significant increase in CKD risk of 5.15(1.77,8.53), 13.62(8.91,18.33) and 31.81(14.03,49.58) when other metals were fixed at the 25th, 50th and 75th percentiles, respectively.ConclusionsCumulative metal exposures, especially double-exposure to serum K and Se may impact CKD risk. Machine learning methods validated the external relevance of the metal factors. Our study highlights the importance of employing diverse methodologies to evaluate health effects of metal mixtures.

Bacterial diversity and biopotentials of Hamtah glacier cryoconites, Himalaya

Cryoconite is a granular structure present on the glaciers and ice sheets found in polar regions including the Himalayas. It is composed of organic and inorganic matter which absorb solar radiations and reduce ice surface albedo, therefore impacting the melting and retreat of glaciers. Though climate warming has a serious impact on Himalayan glaciers, the biodiversity of sub-glacier ecosystems is poorly understood. Moreover, cryoconite holes are unique habitats for psychrophile biodiversity hotspots in the NW Himalayas, but unfortunately, studies on the microbial diversity of such habitats remain elusive. Therefore, the current study was designed to explore the bacterial diversity of the Hamtah Glacier Himalaya using both culturable and non-culturable approaches. The culturable bacterial count ranged from 2.0 × 103 to 8.8 × 105 colony-forming units (CFUs)/g at the different locations of the glacier. A total of 88 bacterial isolates were isolated using the culturable approach. Based on the 16S ribosomal RNA gene (16S rRNA), the identified species belong to seven genera, namely, Cryobacterium, Duganella, Janthinobacterium, Pseudomonas, Peribacillus, Psychrobacter, and Sphingomonas. In the non-culturable approach, high-throughput sequencing of 16S rRNA genes (using MiSeq) showed unique bacterial community profiles and represented 440 genera belonging to 20 phyla, namely, Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, Chloroflexi, Acidobacteria, Planctomycetes, Cyanobacteria, Verrucomicrobia, Spirochaetes, Elusimicrobia, Armatimonadetes, Gemmatimonadetes, Deinococcus-Thermus, Nitrospirae, Chlamydiae, Chlorobi, Deferribacteres, Fusobacteria, Lentisphaerae, and others. High relative abundances of Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes were observed in the samples. Phototrophic (Cyanobacteria and Chloroflexi) and nitrifier (Nitrospirae) in bacterial populations indicated sustenance of the micro-ecosystem in the oligotrophic glacier environment. The isolates varied in their phenotypic characteristics, enzyme activities, and antibiotic sensitivity. Furthermore, the fatty acid profiles of bacterial isolates indicate the predominance of branched fatty acids. Iso-, anteiso-, unsaturated and saturated fatty acids together constituted a major proportion of the total fatty acid composition. High cold-adapted enzyme activities such as lipase and cellulase expressed by Cryobacterium arcticum (KY783365) and protease and cellulase activities by Pseudomonas sp. strains (KY783373, KY783377-79, KY783382) provide evidence of the possible applications of these organisms. Additionally, antibiotic tests indicated that most isolates were sensitive to antibiotics. In conclusion, the present study contributed for the first time to bacterial diversity and biopotentials of cryoconites of Hamtah Glacier, Himalayas. Furthermore, the cold-adapted enzymes and polyunsaturated fatty acids (PUFAs) may provide an opportunity for biotechnology in the Himalayas. Inductively coupled plasma mass spectrometry (ICPMS) analyses showed the presence of several elements in cryoconites, providing a clue for the accelerating melting and retreating of the Hamtah glacier.

Experimental-based groundwater salinization from the carbonate aquifer of eastern Saudi Arabia: Insight into machine learning coupled with meta-heuristic algorithms

Groundwater (GW) salinization of coastal aquifers has become a serious problem for attaining sustainable water resource management in Saudi Arabia and other parts of the world. Therefore, it is crucial to assess the extent of this salinization to protect and manage our water resources effectively. This research proposed real fieldwork GW samples at several locations supported with experimental based on chromatography (IC) and inductively coupled plasma mass spectrometry (ICP-MS) to analyze several GW physical, chemical, and hydro-geochemical elements. In this study, we model GW salinization with machine learning algorithms such as support vector regression, gaussian process regression, artificial neural networks, and least squares ensemble boosting regression tree. The performance of the standalone models was optimized with metaheuristic optimization-based algorithms such as fuzzy hybridized genetic algorithm (ANFIS-GA) and particle swarm optimization (ANFIS-PSO). The outcomes based on three variable input combinations were validated using several performance indicators and graphical methods. The quantitative analysis indicated that GPR-Combo1(MAE=0.006 mg/L), Ensm- Combo2 (MAE=0.025 mg/L), and GPR- Combo3 (MAE=0.078 mg/L) proved merit among the standalone combinations. Where combo 1, 2, and 3 stand for model combinations derived from feature selection. The cumulative probability function (CPF) demonstrated that heuristic optimization ANFIS-GA (MAE=0.0025 mg/L, MAPE=0.19183) and ANFIS-PSO (MAE=0.0018 mg/L, MAPE=0.0723) outperformed the standalone error accuracy and served reliable approach. Both the standalone models and heuristic algorithms used for GW salinization modeling have demonstrated promising results in accurately predicting salinity. This approach could aid in effectively managing the GW resources for sustainable development.

Chemical characterization of road dust during diwali festival in Guwahati city of Assam, Northeast India.

The present study focuses on the elemental analysis of road dust in Guwahati, the largest city of Assam and the largest metropolis of Northeast India during the Diwali festival. Road dust samples were collected on pre-Diwali (PD), the Day after Diwali (DaD), and one week after Diwali (WaD) from two sites (Lankeshwar; LKW and Patharquarry; PTQ). Three composite samples were collected from 3 points at each site. The elemental concentration was analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The concentrations of Ba and Sr increased by 1.6 and 1.7 times, respectively, after Diwali. Among other firework-related elements (FREs), Mg, Al, K, and Cu increased at LKW following Diwali (both DaD and WaD), whereas Mg, Al, and K increased in DaD dust at PTQ. The average concentration of Traffic Related Elements (TREs) at PTQ was significantly higher than at LKW (p < 0.05; 75.40mg/kg vs 63.96mg/kg). Cd had the highest enrichment (EF), followed by Ni and Zn. EF for Cd, Ni, and Zn ranged from high to extremely high enrichment. Ni and Cd exhibited moderate contamination (CF). The ecological risk (ER) values for Cd at LKW and PTQ were 54.32 and 56.71, respectively, indicating a moderate ER. Pearson's correlation was performed to study the relationship between elements, while PCA analysis was used to identify the main sources of these elements. Although the health hazard indices presently do not suggest any immediate danger, hazard quotient (HQ) values for ingestion, inhalation, and dermal exposure were higher for children than adults. In children, the contribution of HQing to HI (total risk) was the highest, accounting for more than 65% of all elements. There is no apparent lifetime cancer risk due to road dust exposure through inhalation.

Exposure to Trace Elements Through &amp;lt;i&amp;gt;Rauwolfia vomitoria&amp;lt;/i&amp;gt; and &amp;lt;i&amp;gt;Argemone Mexicana,&amp;lt;/i&amp;gt; Two Medicinal Plants at Hahotoé-Kpogamé, a Polluted Area in Southern Togo

Background: Herbal drugs and mineral elements are well established for their therapeutic benefits against diseases and nutritional importance in human health. Medicinal plants contain toxic metabolites which, once consumed, become a formidable source of disease. Accumulation of toxic industrial effluents in soil, air and water is continuously increasing due to fast urbanization and intensive environmental pollution. Elements like lead (Pb), cadmium (Cd), uranium (U), arsenic (As) which are not used by the plants directly but accumulate in the plants are detrimental to human health when consumed. This study aims to investigate the level of trace elements through the use of two medicinal plants in a polluted area in southern Togo. The trace elements analysis in the powder of the &amp;lt;i&amp;gt;Rauwolfia vomitoria&amp;lt;/i&amp;gt; and &amp;lt;i&amp;gt;Argemone Mexicana&amp;lt;/i&amp;gt; leaves, was carried out by the method and protocol described by Acme Laboratory using PerkinElmer ELAN 9000 Inductively Coupled Plasma Mass Spectrometry (ICP- MS). The result of trace elements concentrations (ppm) ranges revealed, as follows: Cadmium (0.8-1.5), Antimony (0.17-0.9), Arsenic (10.85-15.25), Lead (11.31-13.33), Iron (21.02-25.13), Manganese (84.5-140), Calcium (22.39-31.81), Zinc (73.1-82.6), Uranium (0.01-0.04) and Thorium (0.15-1.05) are significantly higher than the World Health Organization maximum permissible limit. These results suggested that the leaves of the two medicinal plants have contaminated by the trace elements. More toxicological activities need to be conduct in the area to find out the toxicity level of contaminants in herbal raw materials in the area.

Serum Cobalt Concentration and DNA Methylation Signatures in Women with Obesity

Obesity, a multifactorial disorder, has been associated with alterations in metal metabolismand epigenetic modifications. This pilot case–control study aimed to investigate serum cobalt concentrations and associated DNA methylation patterns in women with obesity. Serum cobalt levels were measured using inductively coupled plasma mass spectrometry (ICP-MS), revealing significantly higher cobalt concentrations in participants with normal weight than in participants with obesity. Additionally, DNA methylation analysis identified differentially methylated positions (DMPs) associated with cobalt exposure, and DMPs between groups highlighted hypomethylation in the top DMPs in individuals with obesity. Functional enrichment analysis of these DMPs unveiled potential pathways implicated in apoptosis, cancer, and metabolic signaling, warranting further investigation into the mechanistic links. This study provides preliminary insights into the interplay between cobalt exposure, DNA methylation, and potential implications for obesity management.

Inflammatory bowel disease alters in vivo distribution of orally administrated nanoparticles: Revealing via SERS tag labeling technique

Nanoparticles (NPs) could be uptake orally and exposed to digestive tract through various sources such as particulate pollutant, nanomedicine and food additive. Inflammatory bowel disease (IBD), as a global disease, induced disruption of the intestinal mucosal barrier and thus altered in vivo distribution of NPs as a possible consequence. However, related information was relatively scarce. Herein, in vivo distribution of typical silica (SiO2) and titania (TiO2) NPs was investigated in healthy and IBD models at cell and animal levels via a surface-enhanced Raman scattering (SERS) tag labeling technique. The labeled NPs were composed of gold SERS tag core and SiO2 (or TiO2) shell, demonstrating sensitive and characteristic SERS signals ideal to trace the NPs in vivo. Cell SERS mapping revealed that protein corona from IBD intestinal fluid decreased uptake of NPs by lipopolysaccharide-induced RAW264.7 cells compared with normal intestinal fluid protein corona. SERS signal detection combined with inductively coupled plasma mass spectrometry (ICP-MS) analysis of mouse tissues (heart, liver, spleen, lung and kidney) indicated that both NPs tended to accumulate in lung specifically after oral administration for IBD mouse (6 out of 20 mice for SiO2 and 4 out of 16 mice for TiO2 were detected in lung). Comparatively, no NP signals were detected in all tissues from healthy mice. These findings suggested that there might be a greater risk associated with the oral uptake of NPs in IBD patients due to altered in vivo distribution of NPs.

Geochemical Characteristics and Sedimentary Paleoenvironment of the Coal-Bearing Strata in the Xishanyao Formation: A Case Study of the Yihua Coal Mine in the Zhundong Coalfield, Xinjiang

The eastern Junggar Basin in Xinjiang harbors abundant coal resources within the Middle Jurassic Xishanyao Formation. However, the formation environment associated with these coal-bearing strata remains unclear. Geochemical characteristics serve as crucial geological indicators of the sedimentary period. Therefore, it is imperative to explore the geochemical attributes and sedimentary context of the coal-rich layers within the Middle Jurassic Xishanyao Formation in the Zhundong region to enhance the prospects of coal extraction and utilization. The elemental compositions, both major and trace, of the Xishanyao Formation were analyzed through X-ray fluorescence spectrometry (XRF) and inductively coupled plasma mass spectrometry (ICP-MS). A comprehensive analysis was conducted on the sediment provenance, tectonic background, and depositional environment of the coal-bearing strata in the Xishanyao Formation. Moreover, through the utilization of a range of discrimination indices, including Sr/Cu, B/Ga, Sr/Ba, V/Cr, Ni/Co, and δCe, the paleo-depositional setting of the coal-containing layers was reconstructed. The findings suggest that the primary source rocks of the coal-bearing beds in the Xishanyao Formation consist of continental tholeiites, with the predominant material composition in the source region being felsic volcanic rocks originating from the upper crust. The tectonic backdrop of the source region is marked by a continental island arc environment. During the sedimentation period of the Xishanyao Formation, the depositional environment was characterized by a freshwater oxidizing setting. Additionally, it experienced a transition from arid-hot to humid-hot before returning to arid-hot conditions.

Chemical composition and trajectories of atmospheric particles at the Machu Picchu Peruvian Antarctic scientific station (62.09º S, 58.47º W)

Antarctica is a remote and relatively pristine region, but the regional transport of aerosols may be a source of pollution, especially in the Antarctic Peninsula. Few studies have characterized atmospheric aerosols and evaluated the contribution of their emission sources. The Peruvian Antarctic research station Machu Pichu (ECAMP, by its Spanish acronym) is located on King George Island in the Antarctic Peninsula. During February 2020, atmospheric particulate mass (PM10 and PM2.5) was sampled and analyzed to characterize its elemental composition and was supplemented by measurements of equivalent black carbon and aerosol size distributions. Chemical elements were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), multivariate techniques, and enrichment factors. The most abundant elements in PM10 and PM2.5 were Na, Fe, Mg, and Si, with the most important local sources being marine (Na, Mg, Mn, Ca) and crustal (Fe, Al, P). Sources of weathering (Ba and Si) from glacial thawing and sources of combustion linked to the use of oil (V) and emission of black carbon were recorded. Air mass back-trajectory analysis using the HYSPLIT model helped identify external sources of particulate matter in the air masses reaching the ECAMP site. Overall, this study supports the growing evidence of the anthropogenic impact of distant and local sources on the white continent.

Commercially available mouthguards: Unearthing trace elements for the first time

The use of mouthguards is advocated by the American Dental Association for orofacial injury prevention and teeth protection. However, the chemical environment in the mouth may cause harmful substances within the mouthguard's polymer material to leach out and be absorbed by the user. Considering this, the present study for the first time analyzed commercially available mouthguards and disclosed the presence of trace elements. Specifically, an analytical method was developed based on closed-vessel microwave-assisted digestion and plasma-based atomic spectrometry for determining toxic trace elements in mouthguard samples. Initially, 75 elements were assessed and, thereafter, quantified cadmium (Cd), copper (Cu) and lead (Pb) in each sample by inductively coupled plasma mass spectrometry (ICP-MS). Method validation was carried out by analyzing a certified reference material of Low-Density Polyethylene, and by addition and recovery experiments. Results for copper were further validated by ICP optical emission spectrometry (ICP-OES). While most samples exhibited elemental levels beneath the method's limit of quantification, Cd, Cu and Pb were detected in four samples. Remarkably, one sample had Cu levels exceeding safe limits by 109 times, highlighting potential toxicity risks. This initial research underscores the need for stricter contamination control in mouthguard materials to minimize potentially health hazards.

A three-mode biosensor for hypoxanthine assay in aquatic products under various storage conditions

Establishing a rapid and accurate method for monitoring the freshness of aquatic products is of great importance. Hypoxanthine has been considered an essential indicator of aquatic products’ freshness. Here, a novel smartphone colorimetric / inductively coupled plasma mass spectrometry (ICP-MS) / photothermal three-mode sensing strategy was established for monitoring hypoxanthine. Hypoxanthine can be catalyzed by xanthine oxidase to H2O2 and uric acid, which can simultaneously degrade MnO2 nanosheets (NSs) to Mn2+. After filter-assisted separation, the smartphone and ICP-MS were performed by monitoring the color of the membrane and the Mn2+ in the filtrate. Additionally, MnO2 NSs can facilitate the oxidation of dopamine to form polydopamine nanoparticles, which exhibit strong photothermal efficiency. The approach successfully monitored the deterioration of aquatic products under various storage conditions through portable thermometers and smartphones with low limits of detection (LODs), providing a potential application for in-situ evaluation of the freshness of aquatic products.

Geochemistry and the optics of geospatial analysis as a preposition of water quality on a macroscale.

The water treatment depends exclusively on the identification of residues containing toxic chemical elements accumulated in NPs (nanoparticles), and ultrafine particles sourced from waste piles located at old, abandoned sulfuric acid factories containing phosphogypsum requires global attention. The general objective of this study is to quantify and analyze the hazardous chemical elements present in the leachate of waste from deactivated sulfuric acid factories, coupled in NPs and ultrafine particles, in the port region of the city of Imbituba, Santa Catarina, Brazil. Samples were collected in 2020, 2021, and 2022. Corresponding images from the Sentinel-3B OLCI satellite, taken in the same general vicinity, detected the levels of absorption coefficient of Detritus and Gelbstoff (ADG443_NN) in 443m-1, chlorophyll-a (CHL_NN (m-3)), and total suspended matter (TSM_NN (g m-3) at 72 points on the marine coast of the port region. The results of inductively coupled plasma atomic-emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) demonstrate that the leaching occurring in waste piles at the port area of Imbituba was the likely source of hazardous chemical elements (e.g., Mg, Sr, Nd, and Pr) in the environment. These leachates were formed due to the presence of coal pyrite and Fe-acid sulfates in said waste piles. The mobility of hazardous chemical elements potentiates changes in the marine ecosystem, in relation to ADG443_NN (m-1), CHL_NN (m-3), and TSM NN (g m-3), with values greater than 20gm-3 found in 2021 and 2022. This indicated changes in the natural conditions of the marine ecosystem up to 30km from the coast in the Atlantic Ocean, justifying public initiatives for water treatment on a global scale.

Quantity and Size of Titanium Particles Released from Different Mechanical Decontamination Procedures on Titanium Discs: An In Vitro Study

Complications such as peri-implantitis could ultimately affect the survival of a dental implant. The prevention and treatment of peri-implant diseases require managing bacterial biofilm and controlling environmental risks, including the presence of pro-inflammatory titanium (Ti) particles in the peri-implant niche. Objectives included the evaluation of the size and quantity of Ti particles released from moderately roughened Ti surfaces during common mechanical surface decontamination methods. One hundred and forty moderately roughened Ti discs were divided into seven groups (n = 20 per group); six groups received mechanical decontamination procedures (ultrasonic scaling (US) with a metal tip and poly-ether-ketone (PEEK) under low and medium power settings, air-polishing with erythritol powder, and Ti brush), and the control group underwent air–water spray using a dental triplex. The rinsing solution was collected for Ti mass analysis using inductively coupled plasma mass spectrometry (ICPMS), as well as for Ti particle size and count analysis under scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS). US metal tip instrumentation generated 34.00 ± 12.54 μg and 34.44 ± 6.08 μg of Ti under low and medium power settings, respectively. This amount of Ti generation was significantly higher than other instrumentation methods. The mean Ti particle size of the US groups ranged from 0.89 ± 0.27 μm to 1.25 ± 0.24 μm. No statistically significant difference was found in the particle size among US groups and Ti brush group (1.05 ± 0.11 μm), except for US with the PEEK tip, where a significantly smaller mean particle diameter was found at the low power setting (0.89 ± 0.27 μm). Mechanical instrumentation can produce Ti particulates and modify the implant surfaces. US using a metal tip generated the highest amount of Ti with smaller Ti size particles compared to all other commonly used mechanical surface instrumentations. The EDS analysis confirmed Ti in PEEK US tips. It can be suggested that deterioration from the PEEK US tip and Ti brush, as observed under SEM, is an additional source of Ti release during Ti surface decontamination.

Carbon aerogel supported Ni–Fe catalysts for superior oxygen evolution reaction activity

AbstractElectrochemical water splitting presents an optimal approach for generating hydrogen (H2), a highly promising alternative energy source. Nevertheless, the slow kinetics of the electrochemical oxygen evolution reaction (OER) and the exorbitant cost, limited availability, and susceptibility to oxidation of noble metal-based electrocatalysts have compelled scientists to investigate cost-effective and efficient electrocatalysts. Bimetallic nanostructured materials have been demonstrated to exhibit improved catalytic performances for the oxygen evolution reaction (OER). Herein, we report carbon aerogel (CA) decorated with different molar ratios of Fe and Ni with enhanced OER activity. Microwave irradiation was involved as a novel strategy during the synthesis process. Inductively coupled plasma mass spectrometry (ICP-MS), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscope (SEM), Energy dispersive X-ray spectroscopy (EDAX spectra and EDAX mapping), Transmission Electron Microscope (TEM), High-Resolution Transmission Electron Microscope (HR-TEM), and Selected Area Electron Diffraction (SAED) were used for physical characterizations of as-prepared material. Electrochemical potential towards OER was examined through cyclic voltammetry (CV), chronoamperometry, and electrochemical impedance spectroscopy (EIS). The FeNi/CA with optimized molar ratios exhibits low overpotential 377 mV at 10 mAcm−2, smaller Tafel slope (94.5 mV dec−1), and high turnover frequency (1.09 s−1 at 300 mV). Other electrocatalytic parameters were also calculated and compared with previously reported OER catalysts. Additionally, chronoamperometric studies confirmed excellent electrochemical stability, as the OER activity shows minimal change even after a stability test lasting 3600 s. Moreover, the bimetallic (Fe and Ni) carbon aerogel exhibits faster catalytic kinetics and higher conductivity than the monometallic (Fe), which was observed through EIS investigation. This research opens up possibilities for utilizing bi- or multi-metallic anchored carbon aerogel with high conductivities and exceptional electrocatalytic performances in electrochemical energy conversion.

Rapid and sensitive determination of trace Cd in carbonate samples using direct solid sampling electrothermal vaporization atomic absorption spectrometry

The accurate determination of cadmium (Cd) hosted and accumulated in sedimentary carbonate remains challenging due to its low concentration (ng·g−1) and complex matrix. Conventional methods, such as inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GF-AAS), which typically rely on liquid sampling and sample digestion, are tedious, labor-intensive and time-consuming. In this study, a rapid and sensitive method for the direct determination of carbonate-hosted Cd was developed based on solid sampling electrothermal atomic absorption spectrometry (SS-ETV-AAS). This method eliminates the need of acid digestion procedure, allowing the entire analysis, including sample preparation, to be completed within 10 min. To minimize the carbonate matrix effect, ethylene diamine tetra acetic acid disodium salt (EDTA-2Na) was proposed as matrix modifier to facilitate the release of Cd, enabling fast and accurate determination of trace Cd in carbonate samples. Under optimized conditions, the Cd detection limits was found to be as low as 0.17 ng·g−1, and repeatability (relative standard deviation, RSD) was better than 8 % (n = 7). The accuracy of the proposed SS-ETV-AAS was verified by analyzing five carbonate certified reference materials (GBW07127, GBW07129, GBW07130, GBW07135 and JDo-1), two soil certified reference materials (GBW07404a, GBW07405), as well as several actual carbonate samples. All these results demonstrate that the proposed SS-ETV-AAS method provides a simple, rapid and sensitive approach for measuring trace Cd in carbonates.

Reference values for plasma and urine trace elements in a Swiss population-based cohort.

Trace elements (TEs) are ubiquitous. TE concentrations vary among individuals and countries, depending on factors such as living area, workplaces and diet. Deficit or excessive TEs concentrations have consequences on the proper functioning of human organism so their biomonitoring is important. The aim of this project was to provide reference values for TEs concentrations in the Swiss population. The 1,078 participants to the SKiPOGH cohort included in this study were aged 18-90 years. Their 24-h urine and/or plasma samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) to determine 24 TEs concentrations: Ag, Al, As, Be, Bi, Cd, Co, Cr, Cu, Hg, I, Li, Mn, Mo, Ni, Pb, Pd, Pt, Sb, Se, Sn, Tl, V and Zn. Statistical tests were performed to evaluate the influence of covariates (sex, age, BMI, smoking) on these results. Reference intervals for the Swiss adult population were also defined. TEs concentrations were obtained for respectively 994 and 903 persons in plasma and urine matrices. It was possible to define percentiles of interest (P50 and P95) for almost all the TEs. Differences in TEs distribution between men and women were noticed in both matrices; age was also a cofactor. This first Swiss biomonitoring of a large TEs-panel offers reference values in plasma and in urine for the Swiss population. The results obtained in this study were generally in line with clinical recommendations and comparable to levels reported in other population-based surveys.

Garnet geochronology, major and trace element geochemistry of the Huanggangliang Fe-Sn polymetallic deposit, NE China

Cu-Fe (Au), W-Sn (Mo), Pb-Zn (Ag) and other element assemblages are common in many skarn deposits, but examples of Fe and Sn coexistence in nature are relatively rare. The Huanggangliang deposit in the southern Great Xing'an Range is the largest Fe-Sn polymetallic deposit in northern China, and there are five main mining areas (SK Ⅰ–SK Ⅴ) distributed along a SW–NE trend. SK Ⅰ and SK Ⅲ are the two larger mining areas in the Huanggangliang deposit, and their mineral assemblages and wall-rocks are significantly different: cassiterite and metal sulfides are duncommon in SK Ⅰ (andesite), while they are widely distributed in SK Ⅲ (marble). Garnet is widely distributed in SK Ⅰ and SK Ⅲ mining areas, and provides a good opportunity to explore the mechanism of Fe-Sn assemblage differentiation. Three types of garnet are distinguishable (Grt 1, Grt 2 and Grt 3) based on their mineral associations, textures and locations, and they mainly belong to the andradite-grossular solid solution series. The LA–ICP–MS U-Pb ages of the garnets from SK Ⅰ and SK Ⅲ are 136.0 ± 1.2 Ma (n = 25, MSWD = 1.9) and 136.2 ± 2.6 Ma (n = 37, MSWD = 1.8), respectively, suggesting that magmatic-hydrothermal activity in these two mining areas began at the same time. Grt 1 (located deep in SK Ⅰ and SK Ⅲ) and Grt 2 (located shallowly in SK Ⅰ) are mainly andradite, while Grt 3 (located shallowly in SK Ⅲ) is mainly grossular. They are all enriched in high field strength elements (HFSEs) and depleted in large ion lithophile elements (LILEs), and their REE patterns are enriched in light rare earth elements (LREEs) and depleted in heavy rare earth elements (HREEs). However, Grt Ⅰ-1a and 1b (deep garnets in SK Ⅰ) exhibit obvious positive Eu anomalies, while the other garnet types exhibit negative or no obvious Eu anomalies. Additionally, Grt 3 has high contents of V, Sn, U, Th, Zn and Y, and low contents of W and Mo. This pattern implies that the garnets in deep SK Ⅰ may have formed under oxidizing conditions with high temperatures, high oxygen fugacity (fO2) and weak acidity, while the garnets in shallow SK Ⅲ formed under reducing conditions with moderate temperatures, moderate fO2 and near-neutral pH. The garnets in shallow SK Ⅰ and deep SK Ⅲ may have formed under weak oxidation–reduction conditions at moderate to high temperatures, moderate fO2 and weakly acidic to neutral pH conditions. Our newly reported field geological, mineralogical, and geochemical data from garnet suggest that the ore-forming fluids of the Huanggangliang were magmatic-hydrothermal fluids mixed with slightly acidic external fluids, chloride complexes may have been the main transport ligands of REEs. The metallogenic environment may be an important factor leading to the difference of mineral assemblages in the Huanggangliang deposit.

Salivary and urinary assessment of fluoride and silver ion concentrations after silver diamine fluoride application in children: a prospective cohort study.

The purpose of the study was to determine the fluoride (F) and silver (Ag) ions levels in the saliva and urine of healthy children after silver diamine fluoride (SDF) application on dental carious lesions. Sixty children (4-6years with ≥ 3 caries lesions) were recruited from the outpatient department of Pediatric Dentistry. From each child, 3ml unstimulated saliva samples were collected at baseline, one hour, and 24h after SDF application. Similarly, 3ml urine samples were collected prior to and after 24h of SDF application. F and Ag ion concentrations were determined by fluoride ion-selective electrode (ISE) and inductively coupled plasma mass spectrometry (ICPMS), respectively. The mean ± standard deviation (SD) baseline, 1-h, and 24-h salivary F concentrations (ppm) were 0.07 ± 0.07, 0.93 ± 0.48, and 0.19 ± 0.19, respectively, while the mean baseline and 24-h urinary F concentrations (ppm) were 0.33 ± 0.20ppm and 0.43 ± 0.25ppm, respectively. The mean baseline, 1-h, and 24-h salivary Ag concentrations (ppb) were 4.22 ± 3.15, 4198 ± 350, and 56.93 ± 37, respectively. The mean baseline and 24-h urinary Ag concentrations (ppb) were 2.80 ± 2.93ppb and 4.72 ± 4.0ppb, respectively. There were statistically elevated F and Ag ion concentrations at 1h and 24h after SDF application as compared to the baseline. Salivary and urinary F and Ag ions concentrations elevated significantly at 24h following SDF applications in children. A significant high recovery of these ions in urine indicates minimal systemic absorption, thus intermittent topical application of 38% SDF has a minimal risk of toxicity.

Glutathionylation of a glycolytic enzyme promotes cell death and vigor loss during aging of elm seeds.

Seed deterioration during storage is a major problem in agricultural and forestry production and for germplasm conservation. Our previous studies have shown that a mitochondrial outer membrane protein VOLTAGE-DEPENDENT ANION CHANNEL (VDAC) is involved in programmed cell death (PCD)-like viability loss during the controlled deterioration treatment (CDT) of elm (Ulmus pumila L.) seeds, but its underlying mechanism remains unclear. In this study, we demonstrate that the oxidative modification of GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE (GAPDH) is functioned in the gate regulation of VDAC during the CDT of elm seeds. Through biochemical and cytological methods and observations of transgenic material [Arabidopsis (Arabidopsis thaliana), Nicotiana benthamiana, and yeast (Saccharomyces cerevisiae)], we demonstrate that cysteine S-glutathionylated UpGAPDH1 interacts with UpVDAC3 during seed aging, which leads to a mitochondrial permeability transition and aggravation of cell death, as indicated by the leakage of the mitochondrial pro-apoptotic factor cytochrome c and the emergence of apoptotic nucleus. Physiological assays and inductively coupled plasma mass spectrometry (ICP-MS) analysis revealed that GAPDH glutathionylation is mediated by increased glutathione, which might be caused by increases in the concentrations of free metals, especially Zn. Introduction of the Zn-specific chelator TPEN [(N, N, N', N'-Tetrakis (2-pyridylmethyl)ethylenediamine)] significantly delayed seed aging. We conclude that glutathionylated UpGAPDH1 interacts with UpVDAC3 and serves as a pro-apoptotic protein for VDAC-gating regulation and cell death initiation during seed aging.